Process and apparatus for use in the manufacture of staple fibers



I y 1940- R. BARTUNEK ET 2,202,477

PROCESS ANb APPA RATUS FOR USE IN THE MANUFACTURE OF STAPLE FIBERS FiledNov. 12, 1938 Patented May 28, 1940 UNITED STATES PATENT OFFICE PROCESSAND APPARATUS FOR USE IN THE MANUFACTURE OF STAPLE FIBERS tion, ware NewYork, N. Y., a corporation of Dela- I Application November 12, 1938,Serial No. 240,018

- In Germany November 15, 1937' 4 Claims.

The present invention relates to the manufacture of artificial fibersand more particularly has for its object to devise -a novel process andapparatus for the cutting of staple fiber.

It isalready known in the art to cut freshly spun artificial silkbundles in a continuous operation, whereby the thread bundles are passedin axial direction through a guiding channel into a rotating disk. Thethread bundle passes the periphery of the rotating disk where it is cutby means of stationary knives. Depending upon the speed of rotation ofthe disk and upon the number of cutting knives arranged around thecircumference of the said disk it is possible to cut the thread bundlesinto staples of varying lengths based upon the operating speed.

It has been found that with the ordinary spinning speed of artificialsilk or staple fiber of 50, or meters per minute the use of only oneknife will cause difficulties if it is desired to cut particularly longstaples, for example, of 12, 15 or 20 centimeters, as is desired forcertain types of staple fiber. It has also been found that due to thelower number of revolutions necessitated by the staple length thecentrifugal force is so small that the fiber bundle is not carriedthrough the guide channel of the centrifugal 4 machine with sufficientforce. Enlargement of the diameter of the centrifugal machine, whichwould naturally result in a higher centrifugal force, is not desired inmost instances, since this change would make the device less suitablefor cutting of short staple lengths.

An improvement in the operation of the machine is made possible if-theguiding channel is thoroughly polished. As long as the cutting isconfined to thread bundles which are moist, i. e., bundles of threadwhich have not been passed through press rollers, the cutting iscomparatively easy because the thread bundles possess a greater weightand consequently develops more centrifugal power which is capable ofovercoming the friction in the guiding channel. If, however, relativelydry thread bundles are cut, 1. e., bundles which have been passedthrough press rollers difiiculties will be encountered even when cuttingcomparatively short staple lengths.

According to the process and apparatus of this invention it has beenfound that the cutting operation of such machines can be improved in a'surprisingly simple manner if compressed air is forced through theguiding channel of the centrifugal machine in the direction of travel ofthe thread bundle.

It is therefore one object of the present invention to devise a processand apparatus whereby the cutting of continuous filaments into shortstaple lengths is facilitated.

Another object of the present invention is to make possible the cuttingof bundles of filaments which are in an approximately dry state.

These and other objects of the present invention will in part becomeobvious and will in part be pointed out in the following specificationand appended claims when taken in conjunction with the attached drawing.In the drawing attached to the specification is illustrated across-sectional view, parts being shown in elevation, of one specificmodification, which may be used in carrying out the invention. In thisparticular apparatus use is made of a stationary blow pipe through whichthe compressed air is forced into the guiding channel of the centrifugalwheel and in the direction of travel of thethread bundle.

Numerous experiments have shown that the unusual effect which can beobtained even with air of moderate pressure (1-3 atmospheres absolute)is apparently partially due to a direct carrying along of the fiberbundle by the air stream, and that a considerable part of this effect isachieved due to the reduction in friction of the fiber bundle in theguiding channel which naturally assists the action of centrifugal forcefor drawing the thread outwardly.

In the drawing accompanying this specification I indicates a base orframe in which is.

mounted a rotatable shaft 2 upon which is mounted the centrifugal wheel3 driven by means of a pulley 4.

Secured to the frame l is a cutting knife 5 which is operativelypositioned with respect to the periphery of the centrifugal wheel 3. Astationary funnel 1 extends into the interior of the guiding channel 5.This funnel is mounted in any suitable manner on a bracket II andprevented from, rotating.

An air supply channel 8 may, as illustrated in the drawing, be cast withthe wall of the funnel I. The channel 8 has mounted at one end a pipeconnection 9 to which the compressed air line (not shown) may beattached. At the other end of the said air supply channel 8 is mounted anozzle l0 having a small opening of approximately a few millimeters atthe outlet and for directing the air stream into the guiding channel 6in the direction of travel of the fiber bundle.

While we reference to the specific structure shown it will be obviousthat our method may be practiced by other means and that various changesin the have described our invention with details of the apparatus may bemade without departing from the spirit and scope thereof in its broaderaspects. Hence it is desired to cover all modifications and forms comingwithin the line or scope of any one or more of the appended claims.

What is claimed is:

1. An apparatus for use in the cutting of fibers comprising a rotatablecentrifuge, a tapered funnel formed centrally of said centrifuge, aguiding channel formed in said funnel and centrifuge, said guidingchannel extending radially to the periphery of said centrifuge, astationary funnel operatively positioned with respect to said firstmentioned funnel, an air channel formed within the wall of saidstationary funnel for directing air into said guiding channel, and atleast one cutting knife operatively positioned with respect to saidcentrifuge and guiding channel.

2. In an apparatus for cutting fibers, the combination of a rotatablewheel having a guiding channel terminating on its periphery, a funnelpositioned coaxially with respect to the wheel and partially extendinginto the guiding channel, said funnel having an air channel formedwithin the wall thereof, and cutting means operatively positioned withrespect to the wheel and the guiding channel.

3. An apparatus for use in the cutting of fibers comprising acentrifugal wheel having a guiding channel terminating on its periphery,

a funnel arranged on said wheel coaxially therewith and leading into thesaid guiding channel, a stationary funnel operatively positioned withrespect to said first mentioned funnel, an air channel formed within thewall of said stationary funnel, means projecting from one end of saidair channel for directing air into said first mentioned funnel, at leastone cutting knife operatively positioned with respect to the wheel andthe guiding channel, and means for driving the wheel.

4. In an apparatus for cutting fibers, the combination of a rotatablewheel having a guiding channel terminating on its periphery, a funnelarranged on one face of said wheel coaxially therewith and leading intothe said guiding channel, a stationary funnel partially extending intothe first mentioned funnel, an air channel formed within the wall ofsaid stationary funnel and in longitudinal direction thereof, meansprojecting from one end of the air channel for supplying air to thelatter, means projecting from the other end of the air channel fordirecting air into said first mentioned funnel, at least one cuttingknife operatively positioned with respect to the wheel and the guidingchannel, and means for driving the wheel arranged coaxially therewith.

RICHARD BARTUNEK. ALFRED MAXTON.

